Hey guys.
I have a 2000 Camry with over 200,000 miles. I have been battling with a persistent P0171 code (System Running Lean Bank 1) as well as a major drop in fuel economy (380 mile range on a full tank of gas down to about 280 at best).
Car has been running pretty weak with noticeable loss in acceleration power; I also notice jerking occasionally and the fluctuating RPM hand confirms that.
I have done a physical check on vacuum lines as well as checks using carb cleaner, nothing tangible. On cold startups I can notice a hissing sound that seems to come from below the engine area but I can’t seem to trace it
I have since changed my MAP sensor (2000 Camry 4-cyl have no MAF sensor), put in a new fuel pump (the whole assembly), poured in Liqui Moly fuel injector cleaner twice, changed my spark plugs. NOTHING.
Will do find a source of that hissing noise try my video using a cigar to find vacuum leaky. And I also realize that at that mileage sometimes the fuel injectors just need replacing because they're too old and worn and get crappy gas mileage a pro would have to check that with a flow meter
